Process for drying fish scrap



June], 1937. A. R. SMITH 2,

PROCESS FOR DRYING FI SH SCRAP Filed Jan. 17, .1936

CYCLONE Ex chm/652 INVENTOR- ALFRED R. TM/TH.

ATTORNEY Patented-June 1, 19 37 UNITED; STATES 2,082,555 mooass ron DRYING FISH sonar Alfred B.

Combustion Engineering York, N. Y.

Smith,.Forest Hills, N. Y.,

assignor to Company, Inc., New

ApplicationJanuary-fl, 1936, Serial No. 59,575

- i 3 Claims.

The present invention relates to the treat ment of fish scrap and the preparation of fish It proposes to use in used heretofore for drying and grinding wet materials, but to modify it in order to overcome some difflculties which, without such modifications, would render such prior process useless for the present purpose. The purpose -of the present invention may therefore be stated to be to modify and adapt such prioinprocess so as to remove certain-difflculties encountered-when the process is applied to materials such as those referred to. In describing the invention reference will be made to the drawing filed herewith showing in a single figure and more or less diagrammatically and partly in section a system utilizing" the improvement. In this type of process the material to be treated is dried and comminuted in a combined drying tower and mill. The drying is accomplished by means of a hot current of air which also serves to convey the material through the tower and mill and thence to a separator. Some materials treated in such systems heretofore and coming ,to the apparatus in very wet state have presented dimcultie's in connection with their being fed to the drying towe They cannot bemoved along in the feeding device in their raw wet state but will merely clog Under the prior practice acertain amount of the dried finished product is returned and intimately mixed with the raw wet supply ior'the purpose of putting the material in such a physical condition that the feeding device can properly move it along 'F'lsh scrap, such as the present invention is concerned with, does not necessar y present this difflculty but could be carried along'by the feed- ,ing device without being mixed with any dry J-It has been found, however, that when 'the fish .scrap is exposed to the current of hot gases in the drying tower and mill. fish glue is formed and comes the surface of the particles of finished product.

scrap causing such particles to the sides and bottom of the drying tower-and the surfaces in the mill or to deposit'glue on In either case the resulting extremely difficult to remove and such removal necessitates the shutting down of the plant. By the present invention this difilculty is obvi ated.

mgIn the drawing the to the-sythii'rough the connection i and is carries the scrap particles through a arator 8.

the fan 9 which-is "orth'e pipe. H to the drying tower and mill up such device.

dry return is I as the glue has not fresh raw supply is brought delivered by delivers it through the pipe and mill 5. In the tower it meets a hot current of gases, coming in through the pipe 6, which tower and mill and through the pipe I to the cyclone sep- The current of hot gases is induced by conveniently combined with the mill 5.

it to the mixer-conveyor 2 which 3 to the tower 4 In the cyclone separator the dried material is 10 separated from the gases and delivered by means the pipe 12. The. leave the separator by means oflthe pipe they are delivered to the reheater by pipe vIi to return to the 1 drying tower. the reheater Hi the gases are reheated by means of hot products of combustion delivered from the furnace i5 through the pipe L6 A vent I1- isprovlded at some gas, circuit to permit excess gas to escape atmosphere.

In order to prev nt the comes to the surface of M, leaving it point in this to the glue which forms and the scrap particles in from causing the glue or the material on both to stick to the surfaces I use means such as those used heretofore for another purpose, namely for placing the wet raw material into proper condition for manipulation in the feeding device; 1. e.I return a certain proportion of the finished dried product and mix it with the raw scrap. The amount I use for this purpose is such that the surface of each'particle of the scrap is completely covered with previously dried material when such scrap particles are delivered into the drying tower,'the quantity used being such that the glue as it is liberated is absorbed by the dry material and does not wet the exposed surface of such dry material. The object and action of such quite different from that 4.

therefore of the dry return inthe prior art. In the present case the action of such dry return occurs in the dry ng tower and mill and not in the mixer. formed in the mixer butis the drying tower quantity may required for the\ is regulated in liberated only when responseto a diflerent factor.

The 'dry return is delivered to the mixertended to have such ambit 20 to which it is delivered by the temperature of such finishedproduct before delivering it to bin 25 and conveyor-mixer 2. A supply of cool air is used for this purpose to convey material from pipe I I to a cooling cyclone separator 22. This current of cool air is induced by means such as thefan 23. In cooling the separator the air is separated and leaves by means of'the pipe 24, whereas the solids fall through pipe I 9 into bin 25. By so first cooling the dried material all diffi ulty in the ,mixerconveyor is avoided.

While'in the above I have described the invention as applied specifically to fish scrap and the preparation therefrom of fish meal, I wish it understood that this is meant to be illustrative and not limiting. The invention is evidently applicable to any material exuding glue under and the claims are inas to include all such the conditions referred to,

materials.

What I claim is: 1. The process of drying fish meal and similar rial with some previously dried products consisting of discrete particles which on being heated liberate glue, comprising the steps of coating the particles of the fresh matematerial, suspending the particles so coated in a current of hot gases whereby they are dried and glue liberated is absorbed by the coating, the amount I of said coating being such that the glue is absorbed by the coating without reaching its surface, separating the particles so dried from the hot gases, cooling the dried material, using a part of the cooled dried material for coating the particles of fresh material, and removing the rest of the cooled dried material.

2. The process according to claim 1, the cool-- ing being done by conveying the dried material by means of a current of comprising further the step of separating the material'from the cool gas.

- -3. Theprocess of drying fish meal and similar products consisting of discrete particles which on being heated liberate glue, comprising the steps of coating the particles or the fresh material with some previously dried material, suspending the particles so coated in a current'oi' hot gases whereby they are dried and glue liberated is absorbed by the coating, the amount of said coating being such that the glue is absorbed-by the coating without reaching its surface, and

cool gas, the process separating the particles so dried from the hot 80 gases. ALFRED R. SMITH. 

